Likert ggplot2 Even Number of Responses

likert_even.R

###############################
## Plotting Likert Type Data ##
###############################
##------------------------------------------------------------------------
## Note: Plotting horizontal stacked bar plots in ggplot2 with Likert type
## data is a non-trivial task.  Stacking is not well defined for mixed
## negative/positive values on a bar.  This requires splitting the data
## set into two different parts (positive/negative), plotting each side
## separately, and filling the colors manually.
##------------------------------------------------------------------------


##=============
## Dependencies
##=============
pacman::p_load(wakefield, tidyverse, numform)

##=========================
## generate random data set
##=========================
lvls <- c(
        "Strongly Agree", "Agree", "Somewhat Agree", 
        "Neutral", "Somewhat Disagree", "Disagree", "Strongly Disagree"
    )

set.seed(10)
dat <- wakefield::r_data_frame(200, 
        is_first_gen = r_sample_binary(x = 0:1),
        `Q1. It´s not known, if climate change is real` = likert_7(),
        `Q2. In my opinion, the risks of climate change are exaggerated by activists` = likert_7(),
        `Q3. Climate change is not as dangerous as it is claimed` = likert_7(),
        `Q4. I'm convinced that we can handle climate change` = likert_7(),
        `Q5. I'm not ok with this` = likert_7()
    ) %>%
    tidyr::gather(Question, Response, -is_first_gen)  %>%
    dplyr::filter(Response != 'Neutral') %>%
    dplyr::mutate( 
        Response = factor(sample(Response), levels = rev(lvls[-4])),
        Level = as.integer(Response)
    )


##===================
## Summarize the Data
##===================
## Summarize the data into counts and proportion by group var (question)
sdat <- dat %>%
    dplyr::count(Question, Response, Level, is_first_gen) %>%
    dplyr::ungroup() %>%
    dplyr::group_by(Question, is_first_gen) %>%
    dplyr::mutate(
        prop = n/sum(n),
        Status = case_when(is_first_gen == 0 ~'Peers', TRUE ~ 'First Generation') %>%
            factor(levels = c('Peers', 'First Generation'))
    ) %>%
    ungroup()

##===============================
## Make the levels and colors key
##===============================
high <- '#03A89E' #'darkred'
low <- '#CD7F32' #'blue'
mid <- 'grey90'

levels_key <- data_frame(
    Response = factor(levels(sdat[['Response']]), levels = levels(sdat[['Response']])),
    Level = as.integer(Response)
) %>%
    arrange(Level)

levels_key$type <- c(
    rep('negative', floor(nrow(levels_key)/2)), 
    rep('neutral', nrow(levels_key) %% 2), 
    rep('positive', floor(nrow(levels_key)/2))
)

half_n_levels <- floor(nrow(levels_key)/2) + 1
levels_key$colors <- c(
    colorRampPalette(c(low, mid))(half_n_levels)[-half_n_levels],
    rep(mid, nrow(levels_key) %% 2),
    colorRampPalette(c(mid, high))(half_n_levels)[-1]
)

levels_key$colors <- factor(levels_key$colors, levels = levels_key$colors)


## Add the levels info back onto the Response Key
sdat <- sdat %>%
    dplyr::left_join(levels_key, by = c('Response', 'Level'))
    

## Split the data apart into negative and positive response types
positive <- sdat %>% 
    dplyr::filter(type == 'positive') %>%
    mutate(colors = factor(colors, levels = rev(levels(colors)))) 

negative <- sdat %>% 
    dplyr::filter(type == 'negative')%>%  
    dplyr::mutate(
        prop = -1 * prop
    )

## calculate negative & positive responses data
prop_dat <- sdat %>%
    group_by(Question, Status, type) %>%
    summarize(
        n = sum(n),
    ) %>%
    group_by(Question, Status) %>%
    mutate(
        prop = n/sum(n),
        proploc = case_when(type == 'negative' ~ -1 * prop, TRUE ~ prop)
    ) %>%
    ungroup() %>%
    group_by(type) %>%
    mutate(
        textloc = 1.13 * max(prop) * sign(proploc),
        label = numform::f_prop2percent(prop, 0)
    ) %>%
    split(.$type)
    

##=====================================
## Plot the horizontal stacked bar plot
##=====================================
ggplot() + 
    geom_bar(
        data = positive, 
        aes(x = Status, y = prop, fill = colors),
        position = "stack", 
        stat = "identity"
    )  + 
    geom_bar(
        data = negative, 
        aes(x = Status, y = prop, fill = colors),
        position = "stack", 
        stat = "identity"
    ) +
    coord_flip()  +
    geom_hline(yintercept = 0, color = 'white', size = 1) +
    guides(fill = guide_legend(reverse = TRUE)) + 
    scale_fill_identity(
        labels = levels_key$Response, 
        breaks = levels_key$colors, 
        guide = "legend", 
        name = ''
    ) +
    facet_wrap(~ Question, ncol = 1)  +
    geom_text(
        data = prop_dat$negative, 
        aes(label = label, x = Status,  y = textloc), 
        hjust = 0, color = 'grey60'
    ) +
    geom_text(
        data = prop_dat$positive,
        aes(label = label, x = Status,  y = textloc), 
        hjust = 1, color = 'grey60'
    ) +
    scale_y_continuous(expand = c(0, 0), limits = 1.02 * range(bind_rows(prop_dat)$textloc)) +
    theme_bw() +
    theme(
        panel.grid = element_blank(),
        axis.text.x = element_blank(),
        axis.ticks = element_blank(),
        strip.background = element_blank(),
        strip.text = element_text(hjust = 0, face = 'bold', size = 11),
        panel.border = element_rect(color = 'gray90', linetype = "dashed", fill = NA),
        plot.title = element_text(color = '#734A12'),
        plot.subtitle = element_text(color = '#734A12'),
        plot.caption = element_text(color = 'grey40')
    ) +
    labs(
        x = NULL, y = NULL, 
        title = 'Question Answer by First Generation Status',
        subtitle = 'Some other long winded explanation that might make one seem smarter',
        caption = 'Note: Captions seem more academic'
    )

Note that this only works for even number of categories. For an odd number see: https://gist.github.com/trinker/0260a9dfdd9531f9b90d9fad2f7b4b12

Code based on: http://rnotr.com/likert/ggplot/barometer/likert-plots/

Thanks Tyler!!